No Subject E-Mails From Different Authors Get Grouped
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 I've had a few users complain about emails with no subject heads getting grouped into one email "conversation", mostly on the iPhone iOS. I've seen this also in Mail on Windows 8.1 I guess a simple thing would be to check about turning conversations off, right? Is that even a setting in iOS 8x? 
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 I've even seen this is gmail. I think conversion grouping is solely based off the subject. Cragslist emails get really fun in gmail cause it likes to group everyone's 
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 It's because they share the same subject - there is no other way for an email system to determine that things are the same conversation. There is no "id" field in the emails to otherwise identify them. 

